新托福综合写作范例 　　READING 　　The discovery of penicillin and other antibiotic drugs is the mo、一dramatic medical development of the twentieth century. These new drugs quickly became known as "wonder drugs" because they saved so many lives that were threatened by major forms of infection. The research that LED to their development rested on the belief that chemicals could he found that would destroy specific microorganisms without injuring the human body at the same time. Advances in chemistry and in the knowledge of bacteria quickened the discovery of such chemicals. 　　In . the first of the sulfa drugs. prontosil. was tested clinically on humans and was found to cure blood infections that would otherwise have been fatal. In 1941. the first successful human tests of penicillin were conducted on cases of streptococcus infections. The discovery of penicillin laid the foundation for even more powerful weapons against specific diseases. Within the next decade, researchers identified some 2(N) antibiotic substances that were effective against one or another type of bacteria. One o『the most important was streptomycin. found to be potent against tuberculosis and other infection:that were not affected by penicillin. 　　Antibiotics gave the medical profession powerful tools that could directly fight a very wide range of specific diseases. They made possible the survival of patients during and after surgery. No longer was it necessary to depend largely on the body's own immune system to fight off major infections:could be attacked directly with drugs. Among the most spectacular effects of antibiotics were number of deaths from pneumonia and tuberculosis. 　　LISTENING 　　(Narrator) 　　Now listen to part of a lecture in a biology class. 　　(Professor) 　　As soon”we developed antibiotics, new strains of卜ae宜eria appeared that were resistant to some or all of the drugs. Hospitals started using antibiotics regularly in the 195tk. but resistance started appearing within a few years. Today. one-third of the patients in hospitals are on antibiotics, but antibiotic resistance is increasing the danger of hospital infections-to the point where people are almost safer staying home than going to a hospital. 　　In the forties, penicillin really was a wonder drug. Back then, you could give a patient with bacterial pneumonia ten thousand units of penicillin four times a day and cure the disease. Today, you could give 24 million units of penicillin a day, but the patient might still die. Why? Well, in a way, bacteria are smarter than us. They evolve to counteract any drug we attack them with. A lot of bacteria are now completely resistant to penicillin. 　　Bacteria can evolve very effective weapons against antibiotics. Some o「them develop enzymes to match every antibiotic we throw at them. All these weapons and counter-weapons match one another-just like the weapons in real military warfare. So. no matter what antibiotic we use, the bacteria will come up with a way to make it useless. 　　How does this happen? Well, if you douse a colony of bacteria with an antibiotic, the colony will be killed-that is. all except for a few cells. A few cells will survive because they carry a resistance gene for that particular antibiotic. The surviving cells quickly multiply, and they pass along this lucky gene to their offspring. And soon you have a new strain of bacteria that's resistant to that drug. 　　One consequence of antibiotic resistance is the reappearance of tuberculosis as a major illness. Twenty years ago, doctors thought tuberculosis was a defeated disease. Since then, however, new cases of tuberculosis have increased by 20 percent. And several strains of the disease are resistant to any drug we can attack them with. 　　(Narrator) 　　Summarize the main points made in the lecture, explaining how they differ from points made in the reading. 　　
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